Wireless Sensor Networks (WSNs) are distributed embedded systems composed of a large number of low- cost, low-power, multifunctional sensor nodes. The sensor nodes are small in size and communicate wirelessly in short distances. These tiny sensor nodes can perform sensing, data processing and communicating. They are densely deployed in the desired environment.
A sensor network consists of multiple detection stations called sensor nodes, each of which is small, lightweight and portable. Every sensor node is equipped with a transducer, microcomputer, transceiver and power source. The transducer generates electrical signals based on sensed physical effects and phenomena. The ...view middle of the document...
The key advantage of WSN is the ability to gather useful information from the physical environment and communicate the same to more powerful devices that can process it. The purpose of the wireless sensor networks is to translate the information provided by the environment into digital form, collect and provide it to other computers.
A dense deployment of many nodes covering the same location creates redundancy which provides greater fault tolerance. Again multiple nodes may send the same information to the sink wasting bandwidth and energy.
Sensor nodes either run on batteries or harvest for energy and once deployed they are unattended and expected to operate for a long time. Their energy resources are limited. Thus it is crucial to use it efficiently to extend the network lifetime and service the application.
The energy constraints are more fundamental than the limited processor bandwidth and memory in sensor networks. Energy constraints are unlikely to be solved in the near future with the slow progress in battery capacity and energy scavenging. Moreover, the unattended nature of sensor nodes and the hazardous sensing environment rules out the possibility of replacement. For these reasons, energy awareness becomes the key research challenge for sensor network protocol design. Several researchers have addressed energy conservation recently. In this paper, the system design and implementation architecture is proposed to increase sensor network lifetime for target tracking. The purpose of the system is to support the ability to track the position of moving targets in an energy efficient manner with low energy consumption for the sensing nodes in the network and to extend the life time of a sensor network. This system is the designed architecture of an energy efficient target tracking system using acoustic sensors and photoelectric sensors. It also uses sleep mode and active mode for each acoustic sensor to make these acoustic sensor nodes save their important energy.
Mobile target tracking
Target Tracking Target detection, classification and tracking are the important applications in WSNs. In a target tracking system, a moving target such as a vehicle or a person which passes through wireless sensor network can be tracked using multiple modalities, acoustic, light, seismic, etc. of the sensors. There are centralized and distributed approaches for target tracking in WSN. In a centralized target tracking system, sensors in the sensing network detect the target and send the target signatures to the Base Station (BS) that is also a sensor connecting to a laptop
or a processing unit. BS determines whether there is a target or not by using the target signatures sent from the sensing nodes and tracks if there is the target. There may be many sensor nodes transporting the target information to BS at the same time. Therefore, this centralized approach causes the data receiving sensor at BS to die easily because of the...